Determination of sea surface temperatures from microwave and IR data

Microwave measurements from the Nimbus 7 SMMR were used to derive the atmospheric precipitable water, which was then used to obtain the atmospheric correction for use with AVHRR thermal IR measurements to obtain sea surface temperature (SST). The resulting SST's were compared with the NOAA operational sea surface temperature measurements, and the two sets of measurements were found to be in reasonable agreement. The average residuals between the two sets of measurements was 0.15 K with the NOAA operational SST's being slightly greater

Recovery of atmospheric refractivity profiles from simulated satellite-to-satellite tracking data

Techniques for recovering atmospheric refractivity profiles from simulated satellite-to-satellite tracking data are documented. Examples are given using the geometric configuration of the ATS-6/NIMBUS-6 Tracking Experiment. The underlying refractivity model for the lower atmosphere has the spherically symmetric form N = exp P(s) where P(s) is a polynomial in the normalized height s. For the simulation used, the Herglotz-Wiechert technique recovered values which were 0.4% and 40% different from the input values at the surface and at a height of 33 kilometers, respectively. Using the same input data, the model fitting technique recovered refractivity values 0.05% and 1% different from the input values at the surface and at a height of 50 kilometers, respectively. It is also shown that if ionospheric and water vapor effects can be properly modelled or effectively removed from the data, pressure and temperature distributions can be obtained

Simulation of radiometer data from a spin stabilized satellite

The effect of misregistration on cloud brightness threshold is investigated by simulating radiometric data as observed from a spin stabilized synchronous satellite such as the SMS. Clouds were introduced randomly and a bidirectional reflectance model was used to create radiance data from clouds and ocean. A theoretical and an empirical reflectance model were compared

Semiparametric Inference and Lower Bounds for Real Elliptically Symmetric Distributions

This paper has a twofold goal. The first aim is to provide a deeper understanding of the family of the Real Elliptically Symmetric (RES) distributions by investigating their intrinsic semiparametric nature. The second aim is to derive a semiparametric lower bound for the estimation of the parametric component of the model. The RES distributions represent a semiparametric model where the parametric part is given by the mean vector and by the scatter matrix while the non-parametric, infinite-dimensional, part is represented by the density generator. Since, in practical applications, we are often interested only in the estimation of the parametric component, the density generator can be considered as nuisance. The first part of the paper is dedicated to conveniently place the RES distributions in the framework of the semiparametric group models. The second part of the paper, building on the mathematical tools previously introduced, the Constrained Semiparametric Cram\'{e}r-Rao Bound (CSCRB) for the estimation of the mean vector and of the constrained scatter matrix of a RES distributed random vector is introduced. The CSCRB provides a lower bound on the Mean Squared Error (MSE) of any robust $M$-estimator of mean vector and scatter matrix when no a-priori information on the density generator is available. A closed form expression for the CSCRB is derived. Finally, in simulations, we assess the statistical efficiency of the Tyler's and Huber's scatter matrix $M$-estimators with respect to the CSCRB.Comment: This paper has been accepted for publication in IEEE Transactions on Signal Processin

Serological diagnosis of pulmonary aspergillosis

Methods for the preparation of antigens from clinically isolated cultures of Aspergillus were standardized. Sera from 25 suspected cases of pulmonary aspergillosis were tested against antigens prepared by us, from 4 strains of A. fumigatus and one strain of A. flavus, using the Ouchterlony double diffusion and immunoelectrophoretic techniques. Of the 25 sera tested, 18 reacted positively with antigens of A.fumigatus, one with A.flavus and 2 with both these species. Antigens of two non-pathogenic Aspergilli included in the study failed to react with any of the sera. Our antigen preparations gave more numerous as well as sharper precipitin lines than the commercial Bencard antigens which were used for comparison. Moreover, mycelial antigens from 48 to 96 h old cultures revealed precipitin lines comparable to that of the routine, 4 week old culture filtrate antigens, thus suggesting that the incubation period for obtaining antigens could be cut down considerably

Experimental Study of Perforated Pin Fins with Perforations around the Circumference of the Fins

Nine fins with inline arrangement and eight fins in staggered arrangement with each fin having the diameter of 16 mm and the perforation diameter of 3 mm are modeled to study the heat transfer performance. The Nusselt number for staggered perforated fins is obtained in the range of 90 to 235 while for solid pin fins in the similar arrangement, obtained in the range of 80 to 220 with Reynolds number in the range of 15000 to 82,000. The convective heat transfer coefficient in case of perforated fins with staggered arrangement is obtained in the range of 25 to 60 W/m2K while for solid pin fins, it in the range of 20 to 50 W/m2K. Overall analysis showed perforated pin fins with staggered arrangement performed better in terms of heat transfer as compared sold pin fins

Highly Selective, Electrically Conductive Monolayer of Nanoparticles on Live Bacteria

Using specific peptide−bacteria affinity, a monolayer of 30 nm Au particle is selectively deposited on live bacteria surface to produce electrically conducting bridges spanning over 12 μm. The conductivity of the monolayer network is further improved by over 10-fold by “electric-field annealing”. The annealing process is explained by a percolation model

Synthesis, spectral characterization and some biological studies of transition metal complexes with Schiff base ligand containing N,O and S as donor atoms

Transition metal complexes of Cu(II), Co(II), Ni(II), Zn(II), Cd(II) and Mn(II) have been synthesized with the Schiff base ligand 5-Sub-N-(2-mercaptophenyl)salicylideneimine. Elemental analysis of these complexes suggest that these metal ions forms complexes of type ML(H2O)stoichiometry for Cu(II), Co(II), Ni(II), Zn(II), Cd(II) and Mn(II). The ligand behaves as tridentate and forms coordinate bonds through O, S and N atoms. Magnetic susceptibility, IR, UV – Visible, Mass and ESR spectral studies suggest that Cu(II), Ni(II) complexes posses square planar geometry, whereas Co(II), Zn(II), Cd(II) and Mn(II) complexes posses tetrahedral geometry. The complexes were tested for their antimicrobial activity against the bacterial strains Staphylococcus aureus and Bacillus subtilis.The Schiff base metal complexes evaluated for their antifungal activity against the fungi A. niger and C. oxysporum. The DNA cleavage studies of Schiff base complexes werestudied using Calf – Thymus DNA by agarose gel electrophoresis method

AlPO4-C Composite Coating on Ni-based Super Alloy Substrates for High Emissivity Applications : Experimentation on Dip Coating and Spray Coating

High emissivity coating was developed on Ni-based super alloy substrates by dip coating and spray coating technique using a chemical precursor sol. The coating material was characterised thoroughly by XRD, SEM, TEM and XPS analyses. Characterisation results showed the presence of nano carbon in the AlPO4 matrix which imparted high emissivity to the coating. Emissivity of the coating varied from 0.6 to 0.9 in the wave length range : 2 µm - 25 µm depending on the thickness of the multilayered coating. Spray coating was very effective for coating the bigger substrates and TPS panels. Emissivity offered by the spray coated substrates was little lower compared to the dip coated substrates. Emissivity offered by the spray coated substrates was little lower compared to the dip coated substrates. Cyclic oxidation performances of the coated substrates at 800 °C and 1000 °C for 100 hrs of thermal exposure were recorded and compared with that of the bare substrate. The emissivity coating was found to offer substantial oxidation resistance to the base substrate at high temperatures